Rico....you have much more insight into the bowling industry as me and probably have forgotten more about bowling than I will ever know, but...as a Risk Manager at a bank, I know that you have to have limits and cutoffs and you have to stick to those numbers. If the USBC allows someone to exceed the diff, than how about the pro that goes over the foul line by 1/32 of an inch? Whether its 1/32 of an inch or 10 feet, the bowler is still over the foul line and trips the buzzer, causing a 0 for that shot. If we would allow a bowler to go past the foul line by 1/32 of an inch, then the next bowler would want it to be ok to go over by 1/16 of an inch, and so on. Once you allow a rule to be circumvented, you allow any rule open for discussion to circumvention and your rules, laws, and regulations lose credibility and are impossible to enforce.
I drilled for years, was on Track staff, Hammer staff, and MoRich staff, and from my time with Mo and Del I know and understand how little .01 diff is, especially with mass bias balls and the super advanced covers we have today, but there has to be a cutoff somewhere, arbitrary or not.